CD4 and infection: Addition of the dual TLR2/TLR4 inhibitor, OxPAPC, significantly reduced the HIV infectivity of CD4+ T cells following infection of PBMC with M. bovis BCG, while addition of the TLR4 inhibitor, CLI-095, showed no effect (Fig 1C), confirming our previous findings that M. bovis BCG infection of PBMC increases the HIV infectivity of CD4+ T cells through a TLR2-dependent mechanism [14].